Thomas Jefferson High School students in Bloomington, Minn., engage in a ‘hybrid’ class, partly taught online, from a cafe. Although the school has now blocked Facebook, it allows other social media in some classes.

Mr. Collins, who teaches at Missouri's Clayton High School, posts between 10 and 15 articles a week on a page he's set up for the class. Students need to read at least one of the articles and write a thoughtful, substantive response that weaves in class material in the comments section below the post.

"I can do things with [the Facebook page] that I absolutely could not do with more mainstream types of teaching," says Collins.

Not surprisingly, Collins was among the many teachers and students who opposed a recent attempt by the Missouri legislature to ban most interactions between teachers and students over social media forums like Facebook. The Missouri law (blocked by a state court in August) was the most sweeping attempt to try to govern the realm of social media in education, but it's hardly unique.

Increasingly, fears over bullying and improper contact with students are prompting districts and schools to try to regulate the vast world of social media – often, say some educators and technology experts, with too heavy a hand, however well intentioned.

"We need to have some sort of rules and guidelines for how you use social media ... but the goal should be to educate our students on what it means to participate in the world in which they live" rather than simply banning certain sites, says William Stites, technology director at Montclair Kimberley Academy in New Jersey and blogger in chief at edSocialMedia, which explores the role of social media in education. "It's meeting students where they are."

Like others, Mr. Stites sees big learning opportunities for students with Facebook, YouTube, Twitter, and numerous other sites, some of which have been designed specifically with teachers in mind.

The bans on certain digital activity may be new, but the fears prompting them regularly arise with new technology, says Steve Jones, a communications professor at the University of Illinois in Chicago. When movies first appeared, he notes, there were efforts to prevent children from going into theaters because of fears that they'd be harmed by both the content and the lack of fresh air.

"There are always some children who need protection, and most children don't need it," he says. "So how do we provide protection and yet keep things sufficiently open, flexible, available, and accessible so that we don't deprive children? It's unclear whether the law can really handle that sort of distinction."

Many of the new policies are sparked by real examples, however rare, of misconduct. The most egregious involve sexual predation (the concern that prompted the Missouri bill), such as the middle school teacher in Pine Hill, N.J., who is accused of conducting numerous inappropriate conversations with male students, in some cases on Facebook.

Other teachers simply use questionable judgment when posting to their Facebook or MySpace page. Several have had their jobs threatened for posting critical statements about their students, including one New York City teacher who, the day after a local sixth-grader drowned at the beach on a school trip, updated her Facebook status to read: "After today, I'm thinking the beach is a good trip for my class. I hate their guts."

Those sorts of scenarios are one reason that statewide education groups in states such as Ohio and Massachusetts have created model policies – in many cases adopted by individual districts – that vigorously regulate social media use by educators.

In Dayton, Ohio, which this fall approved a ban on teachers "friending" students on social networking sites or contacting them by text or instant messages, the head of the local teachers union welcomed the restrictions. This is in marked contrast to the case in Missouri, where the state teachers union sued to block the new law there.

The problem, say critics of such restrictions, is that far-reaching bans – even if they create exceptions for the sort of educational uses Collins set up in his environmental sciences class – often discourage teachers from attempting to use digital media in class at all.

Collins doesn't usually accept direct friend requests from students, but he does often send private messages to them via Facebook to give feedback on their analysis of articles. Any other means of feedback would be cumbersome, he says. "Students don't check e-mail regularly. That is not a part of their world as much as texting and social media messaging," he adds.

Collins and others note that concerns about inappropriate communication often blur the medium with the message, and that teachers' judgment is the key, not how they converse.

Keith Krueger, chief executive officer of the Consortium of School Networking, agrees. "While social networking is the current focus, we don't know what's the next tool. Do we want policy constantly chasing to catch up with the new tool?" he asks. "The focus of policy should be behavior, not the technology."

Virginia initially tried to push a Missouri-like ban on social networking between teachers and students, Mr. Krueger says, but eventually ended up reiterating current state laws against predatory behavior by educators – including on social networking sites – and directing school districts to do professional development around appropriate digital media use.

In Missouri, after a court blocked the original ban, the legislature revised the law to require individual districts to devise their own policies for teachers' social media use and electronic communication.

Teachers like Collins worry that many districts will still create far too draconian bans, and that school boards and administrators will be more concerned with protecting the district than with how the bans might limit educational opportunities.

New Milford does block access to Facebook and Formspring (another social networking site that has been used in a number of cyberbullying incidents) on school computers, although teachers can have Facebook access opened up for a designed lesson. But the school allows all other sites, including ones such as Skype that are often blocked by schools.

"We'd rather prepare our students for how society is structured, as opposed to [using] an education system that's geared for the 20th century," explains Mr. Sheninger.

Don Knezek, CEO of the International Society for Technology in Education, recalls an English teacher explaining how she got better participation when she expanded classroom discussions of literature to the online realm. Shy students, or those who wanted more time to formulate their thoughts, began to "speak" up.

And when Stites, technology director at Montclair Kimberley Academy, takes students on an annual trip to Ireland, part of the curriculum involves building a blog that includes written content, photos, and videos, and then promoting that blog via Twitter. The posts often elicit comments from around the globe.

"We use social media to provide a feedback loop we'd never be able to do if we were constrained to the four walls of the classroom," says Stites.

Still, even Stites believes certain constraints make sense. The social media policy he developed for his school includes a ban on teachers friending students on Facebook or similar sites and discourages them from friending parents as well. It is partly a question of equity – not all students or parents have Facebook accounts – and partly a question of discretion.

He also thinks setting up a Facebook classroom page like Collins's is great – but would want the teacher to make sure all the students are already on Facebook before doing so.

"I don't want to make light of the issues that have come up, because they're real issues," he says. "But we need to make these moments teachable moments. These are lessons our students are going to have to learn, and if not [from] us, then who?"